• We’re currently investigating an issue related to the forum theme and styling that is impacting page layout and visual formatting. The problem has been identified, and we are actively working on a resolution. There is no impact to user data or functionality, this is strictly a front-end display issue. We’ll post an update once the fix has been deployed. Thanks for your patience while we get this sorted.

Need a little math help

B

BigToque

Lifer
image.gif

I need to find the length of line AB and line CD. How would I go about finding it?

The image is horribly done, but it is supposed to be symmetrical 😛

Oh, and point B is not the center of the circle.


Edit:

I updated the image with the information I know. If there is anything obvious I missed you can tell me and I'll add it.
 
Originally posted by: sash1
Originally posted by: jhayx7
Use a ruler? 😕
Click to expand...

yeah, that's about all you can do with that information.

no angle, no fvckin' units even.
Click to expand...

I'm asking what information I would need to calculate the distance. If you can tell me what I need, I can do the rest. I just don't know what I need.
 
Originally posted by: BigToque
Originally posted by: sash1
Originally posted by: jhayx7
Use a ruler? 😕
Click to expand...

yeah, that's about all you can do with that information.

no angle, no fvckin' units even.
Click to expand...

I'm asking what information I would need to calculate the distance. If you can tell me what I need, I can do the rest. I just don't know what I need.
Click to expand...

you need to do it yourself. :evil:
 
are there some options? i mean, there's many diff ways to get this... for example, if you have a right triangle and have the measure of one side and one angle, you can use trig identities to get the other sides (sin = opp/hyp, cos = adj/hyp, tan=opp/adj, etc)... so we need more info or you have to tell us what info we can request...
 
Originally posted by: snoopdoug1
Originally posted by: BigToque
Originally posted by: sash1
Originally posted by: jhayx7
Use a ruler? 😕
Click to expand...

yeah, that's about all you can do with that information.

no angle, no fvckin' units even.
Click to expand...

I'm asking what information I would need to calculate the distance. If you can tell me what I need, I can do the rest. I just don't know what I need.
Click to expand...

you need to do it yourself. :evil:
Click to expand...

you need the radius length and any of the angles that is the trianlgle is a part of (besides the part that touches the circle).

If you have that, you can solve is with trig equalities and such.
 
It IS solvable with current information.

Define a 90 degree arc of the circle with one leg of it passing through B and the other leg parallel to CD. Then each side is 24" long, and you cut in half the distance along that long hunk of circle. Then using assorted trig identities and direct computation based upon the fact that the two sides of your 90 degree wedge are both 24", you can solve for AB and CD uniquely.

An easier way to work it is to do what I just said, but define the top left as the origin (0,0) in a euclidian coordinate system. Then the vertices of the wedge are at (24,0) and (0,-24), and you can solve for the locations of all the other points by enforcing information you have about the distances. From there you just measure the euclidian norm between A and B, C and D. Not a hard problem, but computationally intensive.
 
Originally posted by: Hyperion042
It IS solvable with current information.

Define a 90 degree arc of the circle with one leg of it passing through B and the other leg parallel to CD. Then each side is 24" long, and you cut in half the distance along that long hunk of circle. Then using assorted trig identities and direct computation based upon the fact that the two sides of your 90 degree wedge are both 24", you can solve for AB and CD uniquely.

An easier way to work it is to do what I just said, but define the top left as the origin (0,0) in a euclidian coordinate system. Then the vertices of the wedge are at (24,0) and (0,-24), and you can solve for the locations of all the other points by enforcing information you have about the distances. From there you just measure the euclidian norm between A and B, C and D. Not a hard problem, but computationally intensive.
Click to expand...

I don't think it is. Look at the figure and imagine the angle at point B either being larger or smaller. The rest of the information does not change, but the values of AB and CD do change.

In short, you need to know the angle at point B to solve the problem.
 
You must log in or register to reply here.

TRENDING THREADS

Back
Top